The objectives of this project are: to provide a high-quality sickle cell service program (including public education, detection, counseling and comprehensive clinical care) in order to insure that each patient with sickle cell anemia may attain a high quality of life despite his handicap; to test the feasibility of utilizing nurse practitioners as the primary agent for the delivery of comprehensive health care; to study the natural history of factors, i.e., red cell metabolic status, G6PD deficiency, zinc metabolism, ambient blood viscosity and sickleability, and the severity of sickle cell anemia; to determine whether persons mildly affected with apparent sickle cell anemia possess one or more alpha thalassemia genes.